Floating marker buoys are frequently used by fishermen, boaters, and others to mark specific reference points on the surface of a body of water, or to mark underwater features or objects. The most desired features of these marker buoys are high visibility, convenient use, and self-setting capability to prevent the further release of anchor line after the anchor has completed its descent to the bottom of the water body. In conjunction with the self-setting feature, the marker buoy should have sufficient rotational resistance to prevent further anchor line unwinding and the resultant drifting of the marker buoy due to the forces of wind, waves, or currents. The unit should also be simple and inexpensive to manufacture. Another useful feature is an optional light that can be installed and used in dim light conditions or at night.
There are several types of marker buoys currently on the market. They generally include a floatation unit attached to one end of an anchor line, and the other end of the anchor line is attached to a weighted anchor. One commonly used marker buoy is the barbell or dumbbell shaped unit having eccentric weights to provide rotational resistance to stabilize the marker buoy after the anchor has reached the bottom of the water body. An example of this type is disclosed by Rovner in U.S. Pat. No. 3,653,085, issued on Apr. 4, 1972. Another example is disclosed by Forrest in U.S. Pat. No. 5,376,035, issued on Dec. 27, 1994. Both the Rovner and the Forrest marker buoys have a small (approximately one inch) diameter medial portion on which the anchor line is wound. When the user retrieves the marker buoy, the anchor line is wet, and the user must hold the floatation unit in one hand, while he or she rewinds the anchor line around the medial portion with his other hand. The requisite small diameter of the medial portion and the wet line combine to make rewinding the anchor line a tedious, time consuming, and sometimes-uncomfortable task.
Both of these marker buoy units also incorporate eccentrically positioned weights inside of the floatation spheres to provide rotational impedance to prevent additional anchor line unwinding after the anchor has completed its descent to the bottom of the water body. This torque is needed to resist rotation due to the forces of wind, waves, or currents acting on the floatation unit. The addition of this eccentric weight results in added manufacturing cost and causes the floatation unit to float lower in the water, therefore reducing visibility.
While it would seem desirable to simply increase the diameter of the medial portion (or line storage spool) of currently available dumbbell shaped marker buoys, this would present problems. If, for example, the diameter of the line storage spool were to be doubled to approximately two inches, one would also have to double the eccentric weight in order to provide equivalent rotational impedance to resist further anchor line unwinding due to the forces of wind, waves, or currents. That would increase the weight and cost to manufacture the unit, and the marker buoy would then float ever lower in the water.
To overcome the difficulty of rewinding the anchor line on the small diameter medial portion or line storage spool, the Forrest unit includes an option feature whereby one can use a portable power hand tool to facilitate rewinding the anchor line, but many users may choose to forego using this option because it requires having a power tool on hand.
Another disadvantage is that neither of these two units is designed to be used with attached lights for improved visibility in dim light conditions or at night. Examples of lighted marker buoys are disclosed by Allen in U.S. Pat. No. 5,358,437, issued on Oct. 25, 1994; by Klocksiem in U.S. Pat. No. 4,601,126, issued Jul. 22, 1986; and by Bankston in U.S. Pat. No. 4,544,364, issued on Oct. 1, 1985. The marker unit by Allen requires the use of an unwinding reel that is counterweighted. The marker unit by Klocksiem has the light elements exteriorly mounted on the buoyant body where they are exposed to water and accidental damage. It also requires the use of eccentric weight. The marker unit by Bankston, with its rectangular shape, floats very low on the water surface providing poor visibility, especially if the water surface is choppy.